[PATCH 1/8] iommu/amd: Update event log pointer as soon as processing is complete

[Vasant Hegde <vasant.hegde@amd.com>]

Update event buffer head pointer once driver completes processing. So
that IOMMU can write new log without waiting for driver to complete
processing all event logs.

Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 drivers/iommu/amd/iommu.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index dbe838828efe..e13e401c52de 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -825,10 +825,12 @@ static void iommu_poll_events(struct amd_iommu *iommu)
 
 	while (head != tail) {
 		iommu_print_event(iommu, iommu->evt_buf + head);
+
+		/* Update head pointer of hardware ring-buffer */
 		head = (head + EVENT_ENTRY_SIZE) % EVT_BUFFER_SIZE;
+		writel(head, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
 	}
 
-	writel(head, iommu->mmio_base + MMIO_EVT_HEAD_OFFSET);
 }
 
 #ifdef CONFIG_IRQ_REMAP
-- 
2.31.1